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Rambo Tribble (1273454) writes "A 7-year German study has come to a troubling conclusion: the EM noise from human activities is interfering with birds' magnetic 'compass' [paywalled paper, but above-average abstract], and potentially disrupting migratory behavior. While science is unclear how the birds' compasses work, it is theorized it employs the quantum phenomenon of electron spin. As the lead researcher, Prof Henrik Mouritsen, is quoted as saying, 'A very small perturbation of these electron spins would actually prevent the birds from using their magnetic compass.' The BBC has a nice summary article, as well."

Nowadays, there are over six billion humans living on the planet, and that number is only going up from here. EM radiation? Trust me, that's pretty low on the list of ecological disasters looming ahead for humanity. Terra will keep right on spinning without us; but if we're going to die off from overpopulation you can bet we're going to take as many other higher life forms with us as we can.

So how do we reduce the number of EM wave emitters (number, strength, impact) without causing even more damage to

Fine. But that ecosphere we've been living in will be irremediably altered by the presence of many billions of humans. Our technology will permit our numbers to grow until we have displaced all "naturally occurring" ecosystems (because six billion humans won't stop breeding or living just because the planet is becoming overpopulated). Once that occurs, die-back is the inevitable conclusion; leaving behind an environment fundamentally different from the one we know now.

I had. Slashdot's web server apparently swallowed my post regarding several experiments with rat populations which effectively became 'extinct' or nearly so as a result of overcrowding conditions. Not doing the research twice to have it wiped out again. Google on 'overpopulation experiment' and draw your own conclusions.

So if I read this right, while they are in the presence of electromagnetic fields they can't orient themselves via their internal compass, but the moment they leave that field they regain their orientation. So all they have to do is fly in any direction, and they will eventually get oriented. I'm not sure I see how big a problem this is. It would be unusual for them to experience it in nature, but it seems like something they would naturally recover from.Are their any studies that tell us that large numbers of migratory birds are flying the wrong direction? (as opposed to saying that they might, if they are constantly in an abnormal electromagnetic field)

I wasn't trying to act like an expert.. I was trying to ask a question... You know, to correct for the fact that I only briefly skimmed the article, and because migratory birds are not in any way part of my day to day job.

According to the BBC summary they also orient according to the sun and stars. This disrupts one of three systems. In the US, there's some decent evidence that major landmarks like rivers and lakes are used even by birds that are not water birds, too. It's certainly not a huge problem for most migratory birds. Lack of food sources at their traditional migration times may be much more important.

Pretty much none, nighttime being the time when I'm indoors a lot and sleeping. Even when I'm outside, it's DARK. My inability to see birds flying at night should not be an indicator that birds are not flying at night.

Cornell [cornell.edu] has [birdcast.info] some information you may want to read, as do some [houstonaudubon.org] other [audubonmagazine.org] sources [nytimes.com]. Birds fly before sunrise and after sunset, even in complete darkness. Some species fly right through the night during migration.

I think the bigger problem is that the avian electromagnetic sense is tied to their eyesight. So the electromagnetic noise isn't just causing them to fly in the wrong direction, it's interfering with their ability to see. This may cause them to run into buildings, wind turbines, and power lines more often than usual.

Hmn. My link didn't work, so let's try it here. This is a study on avian electromagnetic vision, with a simulation of what a bird sees when looking at the magnetic field of the Earth.
http://www.ks.uiuc.edu/Researc... [uiuc.edu]

No. Those are the birds who, having been pecked on their entire lives, and misunderstood by the entire flock, have settled into a deep, dark fugue and have decided to end it all rather than giving this unfair universe the satisfaction of screwing them over for one more single fucking day.

A waterfall is very, very far from a 'vertical water surface'. I doubt it the polarization of the light coming off of a waterfall makes it look any more similar to a pool of water than the colored light coming off of it does (that is to say, not at all).

No reason to get snarky, especially when the original post is correct. There are magnetic materials in birds' eyes. However, they only register when exposed to a magnetic field under certain conditions, as a quantum phenomenon. It is an electron spin transfer that is delayed by the quantum Zeno effect to a timescale where the birds' retina can detect the difference.
It's not as simple as a compass that points them in the right direction. Birds use some seriously weird quantum tricks to see magnetic fie